1. Field of the Invention
The present invention relates to the delivery of a shunt and other devices into the myocardium of a patient, and more particularly, to the delivery of a generally L-shaped shunt to provide a bypass through the myocardium from the left ventricle into a coronary artery.
2. Description of the Related Art
Coronary arteries as well as other vessels frequently become clogged with plaque that at the very least impairs the efficiency of the heart's pumping action and can lead to heart attack and death. One conventional treatment for clogged coronary or other arteries is a bypass operation wherein one or more venous segments are inserted between the aorta and the coronary artery. The inserted venous segments or transplants act as a bypass of the clogged portion of the coronary artery and thus provide for a free or unobstructed flow of blood to the heart.
Such coronary artery bypass surgery, however, is expensive, time-consuming and traumatic to the patient. Hospital stays subsequent to the surgery and convalescence are prolonged.
A new coronary artery bypass technique is disclosed in U.S. Pat. No. 5,429,144. That technique utilizes a stent made of a biocompatible material and comprises steps of moving the stent in a collapsed configuration through a blood vessel of a patient's vascular system to the patient's heart, inserting the stent in the patient's myocardium, and upon disposition of the stent in the myocardium, expanding the stent from the collapsed configuration to a substantially tubular expanded configuration so that a blood flow path is formed at least partially through the myocardium.
U.S. Pat. No. 5,755,682 to Knudson discloses an L-shaped shunt (see FIG. 1A of Knudson) having one end in the lumen of an artery facing downstream from an obstruction and the other end in fluid communication with blood within the heart chamber. One problem with using this L-shaped shunt is how to get the shunt into the myocardium without undue trauma to the patient.